Impact crushers

ABSTRACT

An impact crusher of the type having a beater assembly located inside a casing provided with hardwearing liners with which the beaters cooperate, the beater assembly being rotatable about a vertical axis, the impact crusher being provided with a feed assembly comprising a rotatable housing having a series of generally radially extending outlet passages directed towards the hardwearing liners and a duct for feeding material to be crushed into the housing.

United States Patent [191 Acton 1 IMPACT CRUSHERS [76] Inventor: Victor Ernest Henry Acton, 304

Mostyn Hall, Princess Pl.,

Parktown, Johannesburg, Republic of South Africa [22] Filed: Nov. 8, 1972 [21] Appl. N0.: 304,832

[30] Foreign Application Priority Data Nov. 9, 1971 South Africa 71/7547 [52] US. Cl. 241/275 [51] Int. Cl. B02c 19/00 [58] Field of Search 241/186 R, 188 R, 194, 241/275 [56] References Cited UNITED STATES PATENTS 2,392,958 1/1946 Tice 241/275 X 2,798,674 7/1957 Denning.... 241/275 3,150,838 9/1964 Adams 241/275 3,162,386 12/1964 Danyluke 241/275 1 Jan. 14, 1975 3,170,645 2/1965 Behnke et a1 241/275 3,174,697 3/1965 Bridgewater 1. 241/275 3,258,211 6/1966 Behnke 241/275 3,346,203 10/1967 Danyluke 241/275 3,540,667 11/1970 Parker 241/275 3,544,015 12/1970 Gulic 241/275 X 3,578,254 5/1971 Wood 241/275 3,606,182 9/1971 Warren 241/275 Primary Examiner-Granville Y. Custer, Jr. Attorney, Agent, or Firm-Eric H. Waters [57] ABSTRACT An impact crusher of the type having a beater assembly located inside a casing provided with hardwearing liners with which the beaters cooperate, the beater assembly being rotatable about a vertical axis, the impact crusher being provided with a feed assembly comprising a rotatable housing having a series of generally radially extending outlet passages directed to- .wards the hardwearing liners and a duct for feeding material to be crushed into the housing.

7 Claims, 8 Drawing Figures PATENTED N] 4 I975 SHEET 2 OF 2 IMPACT CRUSHERS THIS INVENTION relates to impact crushers and more particularly to impact crushers of the type wherein raw material is crushed when fed into the machine and is pulverized by coming into contact with rotating beaters, the feed being by the action of gravity.

More particularly the invention relates to such impact crushers which have their axes vertical with horizontal beaters mounted on a rotatable shaft within a casing for the machine, hardwearing liners being provided adjacent the beaters to withstand the abrasive action of the material being crushed on the walls of the casing.

It is the object of this invention to provide an impact crusher of the above type wherein the feed to the crusher is improved over presently used feeds and gives rise to added crushing of the feed material.

In accordance with this invention there is provided an impact crusher of the above general type wherein the feed assembly includes a downwardly extending duct adapted to feed material to be crushed into a central housing rotatably mounted within the casing of the crusher, said housing having a plurality of open ended outwardly extending passages.

Further features of the inventionprovide for the housing to be rotatable in unison with the beaters of the crusher, for the passages to be defined by two spaced plates interconnected by a plurality of outwardly extending vanes, for the vanes to extend in a radial direction, and for the housing to comprise an inlet duct secured to the upper plate and terminating a short distance below this plate.

Still further features of the invention will become ap parent from the following description of one embodiment thereof. In this description, reference will be made to the accompanying drawings in which:

FIG. 1 is a plan view of the crusher showing the feed mechanism with the top plate thereof removed;

FIG. 2 is a sectional elevation of the crusher;

FIG. 3a is a detail of the beaters showing the mounting thereof, in section, FIG. 3b is an end sectional view of a beater; and FIG. 3c is an elevation view of a beater.

FIG. 4 is a part-sectional isometric view of the feed distribution device;

FIG. 5 is an elevation of the inside of a channel shaped vane; and

FIG. 6 is a plan view of part of a wear resistant liner for use in the crusher.

In this embodiment of the invention, the crusher comprises a rectangular casing 1 having a removable top cover plate 2 and a centrally mounted circular bowl 4 carrying the wear resistant liners 5 in a circular arrangement.

A rotatable vertical shaft 6 co-axial with the bowl 4 carries at its upper end a beater assembly 7 and above it, a feed distribution device according to the invention.

In this embodiment of the invention the feed distribution device comprises a pair of spaced circular plates 8 and 9 interconnected by means ofa plurality of radially extending vanes 10. The lower plate 9 is secured to the shaft 6 such that it rotates in unison therewith, while the upperplate 8 is provided with a central hole into which extends a short length of duct 11 terminating a short distance below the upper plate 8. The vanes have their inner ends 12 roughly flush with the outside of this duct 11 while their outer ends 13 are flush with the outer peripheries of the plates 8 and 9. Thus the vanes and spaced plates together with the duct 11 define a housing having a plurality of substantially radially extending outlet passages which are directed towards the liners 5.

Leading into this duct 11 is a co-axial tube 14 extending through the cover plate 2 and terminating at its upper end in a hopper 15.

Preferably, the beater assembly 7 comprises a pair of spaced discs 16 between which are pivotally mounted a series of beaters 17 at the peripheries of the discs. The discs thus define an annular passage with the liners 5 into which the pivotally mounted beaters extend.

Also, the bowl is preferably made adjustable in height as described in my co-pending US. Pat. Ser. No. 304,827 of even date so that the wear may be more evenly distributed over the height of the wear resistant liners. As seen in FIG. 2, the liners 5 are one-piece elements which are continuous in height throughout the height of the beater assembly and the feed distribution device.

For convenience sake, the cover plate 2 is pivotally mounted to the casing and is provided with a hydraulic jack 18 to facilitate opening thereof when necessary for inspection or maintenance.

In order to further reduce abrasive wear of the feed distribution device and wear resistant liners, these are made as follows. The vanes 10, of the feed distribution device, being the parts to suffer the major part of the wear, are made of channel sectioned members with the channels opening in the direction of rotation of the device as indicated by arrow A in Fig. 4. The dimensions of the channel are such that the web and flanges thereof extend over the parts of the device along which the majority of feed material passes. The web and flanges are each provided with a series of metal strips 19 welded thereto such that they are inclined towards the center of the distribution device. These strips are spaced such that the spaces between them fill up with feed material which then remains static and further feed material will then simply wear against this static feed material. Thus, the major portion of the wear is effected on feed material instead of vanes and adjacent areas of the plates.

In a similar manner, the wear resistant liners may be made to a sawtoothed configuration in cross-section as indicated by numeral 20 in FIG. 6. Again, in this instance, the depressions fill up with material being crushed which takes up some of the wear which would otherwise be taken up by the liners themselves.

In use, presized feed material which may be crushed rock or minerals is fed into the hopper while the shaft and associated parts are rotating at the predetermined speed. The feed material falls through the tube 14 into the duct 11 and, when it strikes the lowerplate 9, is flung outwardly under the action of centrifugal force and through one of the passages defined by the vanes. Owing to the presence of the latter, the material leaves the passage at high velocity and strikes the liners at roughly right angles, thereby utilizing substantially all of its kinetic energy to initially crush the material prior to its becoming pulverized by the beaters. The material then falls into the beaters and is pulverized thereby prior to falling from the bottom of the casing.

It is to be noted that the crusher is particularly suitable for use where fine dust created during the pulverizing of the material is to be removed in an airstream through the crusher. This is due to the fact that a relatively small annular passage is provided between the discs 16 and liners and thus only a relatively small volume of air is required to remove the dust in comparison with prior similar crushers. Also, it has been found that the crusher of this invention produces a good quality sand from suitable feed material. In this case, as in others, wet feed material may be used without hindering the operation of the machine, although it may be necessary to provide a stream or spray of wash water to remove the sand from the wear resistant liners.

The invention therefore provides a useful and effective impact crusher having an improved yet simple feeding device.

I claim:

1. An impact crusher comprising: a stationary casing having a geneally upright cylindrical bowl; a rotatable beater assembly located within said bowl, said beater assembly including a plurality of substantially horizontal radially extending elongate blades rotatable about a vertical axis; carrier means pivotally supporting said beater assembly; and a material feed assembly located above said beater assembly and coaxial with the pivotal axis of said beater assembly, said feed assembly including a vertical duct having means at the upper end thereof for infeed of material, a rotatable housing encompassing the lower outlet end of said duct, said housing having a plurality of open-ended radially outwardly extending passages for ejecting material therefrom toward the inner annular surface of said bowl, said feed assembly housing including two spaced radially extending plates and a plurality of radially extending vanes interconnecting said plates and defining said passages therewith, said vanes including a series of transversely extending strips thereon, said strips being spaced apart along the length of each said vane.

2. An impact crusher as claimed in claim 1 wherein said strips are positioned adjacent the leading side of each of said vanes.

3. An impact crusher as claimed in claim 2, said strips being each inclined toward the central axis of rotation of said housing.

4. An impact crusher as claimed in claim 1, said feed assembly housing being rotatable in unison with said beater assembly.

5. An impact crusher comprising: a stationary casing having a generally upright cylindrical bowl; a rotatable beater assembly located within said bowl, said heater assembly including a plurality of substantially horizontal radially extending elongate blades rotatable about a vertical axis; carrier means pivotally supporting said beater assembly; and a material feed assembly located above said beater assembly and coaxial with the pivotal axis of said beater assembly, said feed assembly including a vertical duct having means at the upper end thereof for infeed of material, a rotatable housing encompassing the lower outlet end of said duct, said housing having a plurality of open-ended radially outwardly extending passages for ejecting material therefrom toward the inner annular surface of said bowl, and a vertically extending short cylindrical duct portion secured to said rotatable housing and communicating with the radially inner ends of said passages.

6. An impact crusher as claimed in claim 5, said feed assembly housing being rotatable in unison with said beater assembly.

7. An impact crusher comprising: a stationary casing having a generally upright cylindrical bow]; a rotatable beater assembly located within said bowl, said heater assembly including a plurality of substantially horizontal radially extending elongate blades rotatable about a vertical axis; carrier means pivotally supporting said beater assembly; and a material feed assembly located above said beater assembly and coaxial with the pivotal axis of said beater assembly, said feed assembly including a vertical duct having means at the upper end thereof for infeed of material, a rotatable housing en- I compassing the lower outlet end of said duct, said housing having a plurality of open-ended radially outwardly extending passages for ejecting material therefrom toward the inner annular surface of said bowl, and hardwearing liners located within said bowl and annularly encompassing said beater blades and said feed assembly, said hard-wearing liners being one-piece elements which are continuous in height throughout the height of said beater blades and said feed assembly. 

1. An impact crusher comprising: a stationary casing having a geneally upright cylindrical bowl; a rotatable beater assembly located within said bowl, said beater assembly including a plurality of substantially horizontal radially extending elongate blades rotatable about a vertical axis; carrier means pivotally supporting said beater assembly; and a material feed assembly located above said beater assembly and coaxial with the pivotal axis of said beater assembly, said feed assembly including a vertical duct having means at the upper end thereof for infeed of material, a rotatable housing encompassing the lower outlet end of said duct, said housing having a plurality of open-ended radially outwardly extending passages for ejecting material therefrom toward the inner annular surface of said bowl, said feed assembly housing including two spaced radially extending plates and a plurality of radially extending vanes interconnecting said plates and defining said passages therewith, said vanes including a series of transversely extending strips thereon, said strips being spaced apart along the length of each said vane.
 2. An impact crusher as claimed in claim 1 wherein said strips are positioned adjacent the leading side of each of said vanes.
 3. An impact crusher as claimed in claim 2, said strips being each inclined toward the central axis of rotation of said housing.
 4. An impact crusher as claimed in claim 1, said feed assembly housing being rotatable in unison with said beater assembly.
 5. An impact crusher comprising: a stationary casing having a generally upright cylindrical bowl; a rotatable beater assembly located within said bowl, said beater assembly including a plurality of substantially horizontal radially extending elongate blades rotatable about a vertical axis; carrier means pivotally supporting said beater assembly; and a material feed assembly located above said beater assembly and coaxial with the pivotal axis of said beater assembly, said feed assembly including a vertical duct having means at the upper end thereof for infeed of material, a rotatable housing encompassing the lower outlet end of said duct, said housing having a plurality of open-ended radially outwardly extending passages for ejecting material therefrom toward the inner annular surface of said bowl, and a vertically extending short cylindrical duct portion secured to said rotatable housing and communicating with the radially inner ends of said passages.
 6. An impact crusher as claimed in claim 5, said feed assembly housing being rotatable in unison with said beater assembly.
 7. An impact crusher comprising: a stationary casing having a generally upright cylindrical bowl; a rotatable beater assembly located within said bowl, said beater assembly including a plurality of substantially horizontal radially extending elongate blades rotatable about a vertical axis; carrier means pivotally supporting said beater assembly; and a material feed assembly located above said beater assembly and coaxial with the pivotal axis of said beater assembly, said feed assembly including a vertical duct having means at the upper end thereof for infeed of material, a rotatable housing encompassinG the lower outlet end of said duct, said housing having a plurality of open-ended radially outwardly extending passages for ejecting material therefrom toward the inner annular surface of said bowl, and hard-wearing liners located within said bowl and annularly encompassing said beater blades and said feed assembly, said hard-wearing liners being one-piece elements which are continuous in height throughout the height of said beater blades and said feed assembly. 